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Updated: May 20, 2026
Evaluation of Antimicrobial Activities of Nanoparticles and Nanostructured Surfaces In Vitro
Published on: April 21, 2023
Preparation of controlled nano-MgO and investigation of its bactericidal properties
Keqiang Zhang1, Yi An, Lei Zhang
1Laboratory of Agro-Waste to Resource/Scientific Observing and Experimental Station of Dali, Institute of Agro-Environmental Protection, Ministry of Agriculture, Tianjin 300191, PR China.
Abstract:
Nano-MgO is a good bactericide but with strong alkalinity in water due to its rapid hydrolysis. To control its hydrolysis rate and keep its bactericidal properties, we synthesized nano-MgO microspheres using chitosan-alginate system in this study. The synthesized nano-MgO release-controlled microspheres (nMgO-RCM) were with 0.98-1.20mm of particle sizes. Also, their embedding ratio and loading percentage was 63.52% and 12.27%, respectively. Based on the characterization results, nano-MgO was only observed on surface of the nMgO-RCM. Its release rate from the nMgO-RCM could be controlled by the chitosan-alginate system, and the observed rate constant (k(obs)) increased from 0.0289 h(-1) to 0.0358 h(-1) with the increment of the dosage from 10 mg L(-1) to 80 mg L(-1). Furthermore, the nMgO-RCM could maintain pH value lower than 8.5 and colony counts less than 20 CFU mL(-1) for at least 120 h.
Insights
Researchers developed novel nano-magnesium oxide microspheres (nMgO-RCM) using a chitosan-alginate system. These controlled-release microspheres effectively maintain bactericidal properties while mitigating alkalinity issues, offering a stable antimicrobial solution.
Area of Science:
- Materials Science
- Environmental Science
- Biotechnology
Background:
- Nano-magnesium oxide (nano-MgO) exhibits potent bactericidal activity.
- Rapid hydrolysis of nano-MgO in water leads to high alkalinity, limiting its practical applications.
- Controlling nano-MgO hydrolysis is crucial for sustained antimicrobial efficacy and environmental compatibility.
Purpose of the Study:
- To synthesize nano-MgO release-controlled microspheres (nMgO-RCM) using a chitosan-alginate system.
- To investigate the controlled release characteristics and bactericidal performance of nMgO-RCM.
- To address the challenge of high alkalinity associated with nano-MgO in aqueous environments.
Main Methods:
- Synthesis of nMgO-RCM via a chitosan-alginate embedding technique.
- Characterization of microsphere particle size, embedding ratio, and nano-MgO loading.
- Evaluation of nano-MgO release kinetics and its impact on pH and bacterial counts over time.
Main Results:
- Synthesized nMgO-RCM with particle sizes ranging from 0.98-1.20 mm, an embedding ratio of 63.52%, and a loading percentage of 12.27%.
- Nano-MgO was observed on the surface of the microspheres, indicating successful incorporation.
- Controlled release of nano-MgO was achieved, with the observed rate constant increasing with dosage (0.0289 h⁻¹ to 0.0358 h⁻¹).
- nMgO-RCM maintained a pH below 8.5 and bacterial colony counts below 20 CFU mL⁻¹ for at least 120 hours.
Conclusions:
- The chitosan-alginate system effectively controls the hydrolysis rate of nano-MgO.
- nMgO-RCM demonstrates sustained bactericidal properties while mitigating alkalinity issues.
- These findings present a promising approach for developing stable and effective nano-MgO based antimicrobial agents.
